Cloth clamp



Sept 9, 1930- H. w. BUTTERWQRTH, JR.. ET l- CLOTH CLAMP Filed Oct. 5, 1928 :lis 2 s l.. 9 7 14@ FIlZ-t--E l N VEN TOR'S'.

HARRY W. BUTTEIHWQRTH JR.

ALBERT H. maur.

ATTORNEY.

away;

a portion of Fig.'1, when the pivoted jaw ofV the cloth' clamp is moved under the camy of the tentering machine to its most'open posi-l tion and ready to receive the cloth; Fig.4 is a similar sectional view of the operative parts shown in Fig. 3, after the fabriohas released the pawl and gripped by the jaw; and Fig. 5 isa vertical section showing thepivoted Jaw ina modified form.

The body' 2 of the cloth clamp is integral with the chain link 3, and is extended forward ;Y in the fixed jaw 4 and providedwith the hung arms 5, to the fre'eends/of'which :the adjustable hinged jaw 6l is pivoted at 7. 1 The ii-xed jaw may bronze table sheet 10 suitably-1 secured in position and provided in its top surface in a slot 12 arranged at right angles tothe length of the jaw.; and moreover, the body casting has x its fixed jaw 4slotted at 9 immediately below and in alinement with the-slot 12 in the'tablev plate 10 of the lowerfixed jaw. LAll of these partsvare commento cloth clamps in 'commen cial useand no claimismade to them for novelty, except in so .farA as they are combined with our special improvements .tov constitute :ai: l cloth clamp embodying ourlimprovemevnts..

The adjustable or pivoted j awis provided at the top with an arm' 8 adapted toA be moved by Contact with cams in the pathj o fits travel for moving the j aw 6V into openposition, as shown in Fig. V3, Vfor readily: receiving the fabric -to be treatedyand is also provided with,rearwardlyA extending farms 16,betweenfl which the upper partlof a control pawl 13 is" positioned and by which. the pivoted jaw 6 is controlled. In Figf 5, the pivoted paw is provided with a pad 8` contacting. with Ithe calnfor raising it. L g i I Thev control pawl 13'is pivotedlat its lower part on va pivot pin 14 arranged parallel to the clamping` edges of the jaws'4 and6, said pin. extendingv across the slot 9 in the body 2 imnv mediately below the slotted table plate 10.

The pawl13 extends upwardly through Vthe slot12in the table plate 1() and is adjustable.

thereinin a vertical .plane and hasaAlateral portion V19 adapted to move :downwardly through the said slotby gravity when permitted todo so by the cloth 2O andthe pivoted jawk 6. The upper part of thegpawll is provided with slot 15 4which exerts a caln actionupon a .transversepin17 vand roller 18,. constituting a pin structure .carried inthe free ends to thearms 16and extending transf versely vtlirough the slot, the :alinement of the slot issuchfthat its contacting .edges are ini berprovided with abrass or substantially right angles relation to the direction of movement of the pin structure, whereby the initial opening movements of the pawl and aw are coincident and overlap without interfering contact.

By reference to Fig. 1, itzwill be seen that .whenthe part 19 of the pawl is resting upon the cloth 20, the cam slot 15 is supporting the Vtransverse pin'17 and roller 18`in a position almost above the pivot 14 of the pawl and in such position that a verticalline carried downward at a; will pass close to the pivot 14 and between the said pivot and Contact point g/ of the cloth .retaining portion 19, whereby the pivoted jaw 6 isheld suspended out of gripping ractionupon the cloth but in readi- A ness to automatically grip the cloth-adj acent to the selvage thereof the momentLthe cloth` slides from under the pawl.

In Fig. 3 is shown the position of the pawl 13: andpivoted jaw 61when the llatter i is forcibly moved whenl passingv the operating cam (not shown) of a. tenter or other machine forwhich the cloth clamp4 is adapted. 1n this position, the clamp isinoved over the selvage: of the cloth indicatedwin dotted lines. lNhenthe cam.is passedandthe .parts free to `act under.. gravity,l theypassumev the positions lshown in Fig. 1, inV which. `the cloth 20 supports the pawl and the latterlin turnvsupports thejaw 6. As theclotlr clamp is moved intheV direction `toward` the. selvage of the cloth, thetlatter is .graduallyl withdrawn from under thepawl, releasing the same. When such release takesiplace,xthe pawl. drops and releasesV the: `j aw.v6, Which,. under gravity, movesidownwardzand grips the selvage edge of the cloth as shown in Fig. 4.

y Te'fhavebefore referred to the vfact that the support of the ,cam sl'ot 15 ,of the pawlupon the pin 17 and its roller 18 is in a vertical line ion m passingrelatively close to the .pivot 14 of the pawl.' It will nowbe understood that the leverage of the pawlfrom pivot, 14 tothe verticahline y, whereit Ycontacts with the cloth, issix times as great as the leverage from pivot14 to the vertical linea", and consequently the downward thrust `of thepawl upon the cloth isL approximately only onesixth ofthefdownward pressure of the vjaw 6 upon the 'pawh .Ther-dore, the lightest weight or textureof fabric is strong enough tosustain the down-Ward. thrust of the pawl.

ltwill also be seen that the position of the slot..15 sustains Vthe movable jaw 6 closely abovethe fabric 20when thepawl is` resting upon the cloth andthe actionofuthe transverse pin and roller 18 of thelj aw produces a quick action and imparts a rapid movement to the pawl the moment itisreleased vby the cloth, so: that theljaw Gwinstantly clamps the clotlrclosefto theselvage edge. as indicated ingFig. 4. f f x if .FromV the foregoing, it will'be. understood that the cloth ,clamp is very'zpositive-:in ac- Y tion, and yet the pressure of the pawl upon the cloth isso light that the most delicate fabric may be handledv by a cloth clamp of this nature without being forced through the slot l2 by the action of the pawl and operative weight of the aw controlled by the pawl.`

Heretofore, it has been la common expedient, where the pawl is pivoted above the table, .to provide a notched central nipping edge to furnish clearance spaceforthe end of the pawl and made necessary because, duri ingthe first portion-of its movement, it ad Y` tear the fabric. These defects ari-iovercomel vances toward the jaw under the opening i `movement thereof. This notchingofthenipper Jaw has va tendency to'injure delicate fab-I rics by providing abrupt edges which cut or by, our present improvement by reason of the fact that the pivoting of the control pawl Vlfbelow the level oftheI table of the fixed jaw causes the retainingportion 19,V in being raised to positionshown in Fig. 3, to be moved 'f backward and away from the clamping ]aw or nipper, with the result that they both move in the same direction and hence do not interl `mOvement ofthe pWlWhen the parts are be` ing moved 30` into their receiving position By referring to Figi, itwill be `readily perceived that as the clamping jaw 6 isV i moved upward and `to the left, the retaining portion 19 'of the control pawl will also be moved upward and to the left withamaximum movement to the position shown in Fig. 3;V and as they both move inthe same capacity of the jaw and pawl to be moved in the same direction, the retaining portion y19 Y A cloth clamp of thecharacterstated, com-V prising a body part having a slotted fixed jaw, a pivoted jaw hinged above the fixed jaw `and movable rearward out of gripping rela# tion with the fixed aw, cloth controlled pawl pivoted on an axis below the plane of the gripping surface of the fixed jaw and having a forwardly extending portion movable through the slot Vof thexed jaw and `also having its forward end shaped and positioned with respect to its axis so thatra rising movement causes the said end to `recede from the` pivoted jawf during its backward movement,

and a `close `positive operative connection betweenthepawl and pivoted jaw comprising a slot and a pin structure the width of which slot Vis substantially equal to the diameter of the pin and the alignment of the slot Walls 4are at substantially right Vangles to the direc-` tion of movement ofther pin structure wherebythe initial opening movementof the pawl u and movable jaw are coincident andthe for y ward supporting extension of the pawl moves y with the pivoted jaw in the same direction but at a greater initial speed so as to pass from below to above the gripping edge ofthe pivoted jaw before itsopening `movement can cause the said edge tostrike the pawll In testimony of whichinvention, wefhereunto setour hands. y i a i HARRY' lV. BUTTERWORTH, JR. lALBERT H. MOLT."

u general direction they ywill notinterfere, and u consequently no cutting awayrof the grip-` pingjaw is necessary. By 4reason of this mi i u of the pawl may be shaped to be controlledV by v the fabricV very close to the nipping end of the jaw 6, as shown in Fig. l, and consequent# ly theseparts maybe proportioned to prof` iiof i vide avery close n ip to theselvage edgewith` i `out interference and without 'objectionably i It will nowbe 'apparentthat we have devised ajnovel and'usefulconstructionwhich` y embodies the features offadvantage, enume'r" ated as desirable,andgwhilewe have in the ofthe nippingfedge to permit passage of the retainingpawl.

present instance shown andi-described the i reliableresults, it is y,to be understood that we donot restrict `ourselves to th'ejdetails as the same are susceptible of lmodificatlon. in variwe i claim Patent 1s i preferred embodiment thereof whichhas been found in practice to give 'satisfactoryand' 

